Re: [OSPF] OSPF GR query

[Acee Lindem <acee at cisco.com>]

Hello Amir,

Khan Amir-G20247 wrote:
>  
>
> Hi 
>
> I have query related to OSPF Graceful Restart. 
>
> Consider this scenario: 
>
>  
>
> - Three Routers R1, R2 and R3 connected via Broadcast networks. 
>
>  
>
>  
>
>  
>
> - Where R1 is a DR on both the segments, where as R2 and R3 are in
> DR-other
> - Now R1 wants to perform GR, R2 and R3 agrees to be its Helpers. 
> - Now after restart R1 will try to form adjacency with both R2 and R3. 
> - Lets say R1 and R2 had become FULL, while R1 and R3 had reached
> Exstart state.   Now at this time R2 receives an LSA (any type 1-5 and
> 7, from some other router existing in the same area, not pictured here)
> which he needs to flood to R1. 
> - This will force R2 to quit Helper Status, while R1 and R3 are still in
> process of forming adjacency. 
>   
Since he has reached FULL state, he is no longer a helper router.
> Considering above scenario, my doubts are: 
>
> - How will R1 come to know that its Helper R2 has quit? 
>   
Since he has reached FULL state, he is no longer a helper router.
> - Will the adjacency between R1 and R2 needs to go down, as R2 quits
> helper mode? 
>   
No
> - Will this effect the adjacency formation of R1 and R3?
>   
No. R3 MAY exit helper status and re-originate a new router LSA if he 
receives the new
LSA before reaching FULL state with R1 AND he is has strict-LSA-checking 
configured.

Hope this helps,
Acee
>  
>
> Regards 
> Aamir 
>
>  
>
>
>   
> ------------------------------------------------------------------------
>
> _______________________________________________
> OSPF mailing list
> OSPF at ietf.org
> https://www1.ietf.org/mailman/listinfo/ospf
>   

_______________________________________________
OSPF mailing list
OSPF at ietf.org
https://www1.ietf.org/mailman/listinfo/ospf